JP2019512157A - Mixture of elemental metal and carbon for energy storage - Google Patents

Abstract

The energy storage device comprises a first electrode, a second electrode and a separator between the first electrode and the second electrode, the first electrode or the second electrode comprising elemental lithium metal and carbon particles. The method of manufacturing the energy storage device can include forming a first electrode and a second electrode, and inserting a separator between the first electrode and the second electrode. Here, the step of forming the first electrode or the second electrode includes a step of mixing elemental lithium metal and a plurality of carbon particles. [Selected figure] Figure 7

Description

  The present invention relates generally to an electrode composition for an energy storage device, an energy storage device implementing such an electrode, and related methods.

  Energy storage devices based on lithium, sodium, potassium, magnesium and / or aluminum ions can be used to power a wide range of electrical devices. Batteries and / or capacitors using these materials are used in a variety of applications, including, for example, wind power systems, uninterruptible power systems (UPS), photovoltaic power generation, and / or energy recovery systems for industrial equipment and transport systems. It can be implemented. The electrodes of such batteries and / or capacitors may undergo a pre-doping process during manufacture.

  In some aspects, the energy storage device comprises a first electrode, a second electrode, and a separator between the first electrode and the second electrode, at least one of the first electrode and the second electrode comprising carbon particles and It can contain an elemental metal. The elemental metal comprises elemental lithium metal, can consist essentially of, or consist of elemental lithium metal. The elemental metal comprises elemental sodium metal, may consist essentially of elemental sodium metal, or may consist of elemental sodium metal. The elemental metal comprises elemental potassium metal, can consist essentially of, or consist of elemental potassium metal. The elemental metal comprises elemental magnesium metal, may consist essentially of elemental magnesium metal, or may consist of elemental magnesium metal. The elemental metal may comprise, consist essentially of, or consist of elemental aluminum metal.

  In some embodiments, at least one of the first electrode and the second electrode can comprise a dried electrode film containing elemental lithium metal and carbon particles. At least one of the first electrode and the second electrode can include an anode, such as a lithium ion battery or an anode of a lithium ion capacitor.

  In some embodiments, the carbon particles comprise porous carbon particles, each porous carbon particle having a plurality of pores, at least some of which are at least some elemental lithium metal. accept. In some embodiments, porous carbon particles can include activated carbon. In some embodiments, porous carbon particles can include hierarchically structured carbon. In some embodiments, porous carbon particles can comprise mesoporous carbon.

  In some embodiments, a solid electrolyte interface (SEI) layer can be formed that covers exposed portions of elemental lithium metal. This SEI layer can cover the exposed portion of elemental lithium metal under the outer surface of the corresponding porous carbon particle.

  In some embodiments, the carbon particles comprise graphite particles.

  In some embodiments, the elemental lithium metal can comprise elemental lithium metal particles.

  In some embodiments, a method of manufacturing an energy storage device comprises: mixing an elemental lithium metal and a plurality of carbon particles to form a first electrode film mixture; and forming an electrode film from the electrode film mixture Can be included.

  In some embodiments, the method comprises forming a first electrode and a second electrode, at least one of which includes an electrode film, and inserting a separator between the first electrode and the second electrode. It can further include.

  In some embodiments, the plurality of carbon particles can comprise a plurality of porous carbon particles, each porous carbon particle having a plurality of pores. In some embodiments, the porous carbon particles can include activated carbon. In some embodiments, porous carbon particles can include hierarchically structured carbon. In some embodiments, porous carbon particles can comprise mesoporous carbon.

  In some embodiments, combining the elemental lithium metal and the plurality of carbon particles is elemental such that at least some of the pores corresponding to each porous carbon particle receive at least some elemental lithium metal. A step of mixing lithium metal and a plurality of porous carbon particles can be included.

  In some embodiments, a solid electrolyte interface (SEI) layer can be formed on exposed portions of elemental lithium metal. Forming the SEI layer can include covering the exposed portion of elemental lithium metal underlying the outer surface of the corresponding porous carbon particle. In some embodiments, forming the SEI layer includes exposing exposed portions of elemental lithium metal to the electrolyte solvent vapor. In some embodiments, exposing the exposed portion of elemental lithium to the electrolyte solvent vapor comprises exposing the exposed portion of elemental lithium to the carbonate vapor.

  In some embodiments, the plurality of carbon particles comprises a plurality of graphite particles.

  In some embodiments, the mixture is a substantially homogeneous mixture.

  Some embodiments further include producing a bulk elemental lithium metal and reducing the size of the bulk elemental lithium metal to form a plurality of elemental lithium metal particles.

  In some embodiments, combining the elemental lithium metal and the plurality of carbon particles comprises combining the dry elemental lithium metal and the plurality of dried carbon particles to form a dried electrode film mixture. In some embodiments, at least one of the first and second electrodes comprises an anode of a lithium ion battery or lithium ion capacitor.

  In some aspects, the mixture of bulk materials to form a lithium ion energy storage device can contain elemental lithium metal and activated carbon particles.

  In some embodiments, a mixing device is provided having an internal volume for receiving a bulk mixture comprising elemental lithium metal and activated carbon particles.

  In some embodiments, the mixing device further comprises an inert gas in the internal volume. In some embodiments, the mixing apparatus further includes electrolyte solvent vapor in the chamber.

  In some embodiments, the activated carbon particles comprise graphite. In some embodiments, activated carbon particles comprise porous carbon particles having elemental lithium metal intercalated in the pores.

  In some embodiments, a pre-doped energy storage device electrode can include a mixture of an elemental metal such as lithium and activated carbon particles.

  In some embodiments, an energy storage device is provided. Here, the energy storage device is manufactured by mixing an element lithium metal and a plurality of carbon particles to form an electrode film mixture, and forming a first electrode film from the electrode film mixture. In a further embodiment, the energy storage device further inserts a separator between the first electrode and the second electrode, optionally placing the first electrode, the separator and the second electrode in the housing, optionally further An electrolyte is disposed within the housing and the first and second electrodes are contacted with the electrolyte, and optionally, the second electrode is pre-doped.

  Specific objects and advantages are described herein in order to summarize the advantages of the invention and the prior art achieved by the invention. Of course, it should be understood that not all such objectives or advantages need to be achieved in accordance with a particular embodiment. Thus, for example, one skilled in the art can embody or practice the present invention in a manner that can achieve or optimize one advantage or set of advantages without necessarily achieving other objects or advantages. Will understand.

  All of these embodiments are intended to be included within the scope of the invention disclosed herein. These and other embodiments will be readily apparent to those skilled in the art from the following detailed description with reference to the accompanying drawings. And, the present invention is not limited to any particular disclosed embodiment.

  These and other features, aspects, and advantages of the present specification will be described with reference to the drawings of specific embodiments, which are intended to illustrate the specific embodiments and which are incorporated by reference herein. There is no limitation on

  The present specification includes at least one drawing shown in color. Copies of the color drawings herein are provided by the Office upon request and payment of the necessary fee.

It is a schematic sectional drawing of the energy storage apparatus which concerns on one Embodiment. FIG. 1 is a schematic of porous carbon particles with or without elemental lithium metal in the pores, according to one embodiment. It is the schematic of the porous carbon particle whose expansion magnification is higher than FIG. 2A. FIG. 5 is a schematic view showing an opening corresponding to a hollow channel or pore in porous carbon particles. FIG. 2 is a schematic view of hollow channels or pores in porous carbon particles comprising elemental lithium metal. FIG. 5 is a schematic view showing the opening of the outer surface of porous carbon particles having elemental lithium metal. FIG. 2D is a schematic view showing a SEI layer on exposed lithium metal in the opening of the outer surface of the porous carbon particle shown in FIG. 2D. It is a flowchart of the example of a process of preparing the mixture containing carbon particle and elemental lithium metal. It is a flow figure of the example of a process of manufacturing a plurality of lithium carbon composite particles. It is a flowchart of the example of a process of preparing the mixture containing a graphite particle and elemental lithium metal. FIG. 6 is a flow diagram of an example process for making an electrode film using one or more of the compositions described herein. FIG. 6 is a schematic view of an example of an apparatus configured to combine elemental lithium metal and carbon particles in accordance with one or more steps described herein. It is a photograph which shows one step in the process of forming an electrode film mixture from bulk elemental lithium metal and graphite particles concerning one embodiment. It is a photograph which shows the next step of FIG. 8A in the process of forming an electrode film mixture from bulk elemental lithium metal and a graphite particle. It is a photograph which shows the next step of FIG. 8B in the process of forming an electrode film mixture from bulk elemental lithium metal and a graphite particle. FIG. 6 is a voltage curve illustrating the specific capacity performance of a coin cell including an electrode film formed according to an example. FIG. 6 is a voltage curve illustrating the specific capacity performance of a coin cell including an electrode film formed according to an example.

  Although specific embodiments and examples are described below, one skilled in the art will recognize that the present invention is beyond the specifically disclosed embodiments and / or uses, as well as improvements, etc. Will. Thus, the scope of the invention disclosed herein should not be limited by the specific embodiments described below.

  Disclosed below are embodiments of mixtures of materials, corresponding electrodes, energy storage devices, and related methods, all using elemental lithium metal as a bulk material. As used herein, elemental lithium metal refers to lithium metal in the zero oxidation state. In the use of conventional energy storage devices, such as the use of rechargeable energy storage, elemental lithium metal is not used as a feedstock. By dispersing elemental lithium metal in the components of the electrochemically active material, it is possible to obtain an electrode in which elemental lithium metal is finely distributed, but it is highly reactive or it explodes under certain conditions in the manufacturing process In some cases. For example, in the manufacture of conventional wet energy storage devices, even if lithium elemental metal is highly reactive when it is exposed to water used in wet processing and / or a large amount of liquid such as N-methyl pyrrolidone, it explodes. Because there is no lithium elemental metal. Instead, conventional energy storage devices use lithium materials that are known to have a surface-treated coating layer to provide stability. These lithium materials, such as materials containing lithium cation and carbonate based compositions, have non-zero oxidation states. For example, the conventional method uses Stable Lithium Metalized Powder, a SLMP trademark of FLC Lithium Corporation. These conventional materials often include a coating with a salt, which is split to contact lithium in the secondary processing step, which reduces the energy density of the electrodes formed from these materials, resulting in processing steps Become more complex and material costs increase. The processing and structure of the materials used herein enables the use of bulk elemental lithium metal, thereby increasing the energy density of the resulting energy storage device and, to some extent, the potential for undesirable reactions or explosions. Is reduced.

  By including elemental metal in the mixture of electrode active materials, pre-doped electrodes can be produced. Although this does not intend to limit the scope of the invention by theory, it is believed that lithium metal contained in the electrode film produces free metal ions by a redox reaction. Thus, an electrode comprising an elemental metal as described herein may emit electrons when in contact with the electrolyte and subsequently form a metal cation per lithium metal atom. The released metal ions may diffuse to either electrode. For example, typical anode materials of energy storage devices generally include one or more intercalated carbon components. The intercalated carbon component can be selected such that certain metal ions, such as lithium ions, are intercalated. If the electrode comprises an elemental metal as described herein, the metal ion can be intercalated into one or more active carbon components of the anode. In this regard, for example, the cathode material of the capacitor generally comprises a carbon component capable of adsorbing metal ions, such as lithium ions. When the cathode is in contact with the metal ions, the metal ions may be adsorbed on the surface of the cathode.

  Thus, in some embodiments, the materials and methods presented herein may have the advantage of reducing the number of steps for pre-doping of the electrode. Specifically, if the elemental metal is included in the electrode film mixture, there is no need to perform the separate pre-doping steps required for existing electrode films. The electrode film mixture described herein can enable intimate contact between the elemental metal and the plurality of carbon particles. Thus, the need for a pre-doping step requiring a separate electrical element to provide electrical contact between the source of pre-doping material (which may for example be a metal ion source such as elemental metal or metal ion solution) and a carbon based electrode is not required . Alternatively, embodiments herein can provide a pre-doped electrode with an electrode film containing elemental metal particles that releases metal ions upon contact with an electrolyte in an energy storage device.

  Elemental metals may be less expensive than metal salts suitable as pre-doping sources. The materials and methods presented herein allow for the preparation of pre-doped electrodes without the use of metal salts. In addition, the materials and methods presented herein are compatible with dry electrode manufacturing techniques, thus reducing the processing inefficiencies associated with wet electrode manufacturing. Thus, in some embodiments, the materials and methods provided herein can increase the cost efficiency of manufacturing pre-doped electrodes. It can be appreciated that the elemental metals and concepts related thereto described herein with respect to energy storage devices having lithium can be implemented with other energy storage devices and other metals.

Bulk elemental lithium metal can be provided in sheets, bars, rods, or other forms of elemental lithium metal. In some embodiments, bulk elemental lithium metal may be one or more elements lithium metal piece having a volume greater than about 1 mm ³ containing about 1 mm ³ ~ about 1 m ^3, respectively. In some embodiments, the bulk elemental lithium metal can also be an elemental lithium metal sheet having a thickness of about 5 μm to about 100 μm, including about 10 μm to about 80 μm, or about 50 μm to about 100 μm. Bulk elemental lithium metal can also be lumps of lithium of various shapes. Bulk elemental lithium metal can be further reduced in size to particles, mixed with carbon such as carbon particles, eg, graphite particles, porous carbon particles and / or activated carbon particles, and the like, of energy storage devices Make a bulk material particle mixture to form an electrode. In some embodiments, the elemental metal, eg, lithium, is a powdered elemental metal. In further embodiments, the elemental metal, eg, lithium, is reduced in size during one or more of the processing steps described herein, eg, one or more of steps 300, 400, 500 or 600, and the elemental metal is Form a powder.

As used herein, carbon particles can mean carbon particles of various sizes, such as graphite, including porous carbon particles and / or non-porous carbon particles. In some embodiments, the carbon particles can have a cumulative particle size D ₅₀ of about 1 μm to about 20 μm. In some embodiments, the cumulative particle size D ₅₀ may be about 1 μm to about 15 μm, or about 2 μm to about 10 μm.

  As used herein, porous carbon particles can refer to various carbon materials having pores or hollow channels (hollow tubes) extending therein. In some embodiments, the porous carbon particles can comprise nanoporous carbon particles, microporous carbon particles, mesoporous carbon particles and / or macroporous carbon particles. The pores or hollow channels can have a diameter of about 1 nm to about 2 μm. In some embodiments, the porous carbon particles have a diameter of about 2% to about 10% of the diameter of the particles, including about 2% to about 5% or about 5% to about 10% of the diameter of the particles. It can have pores. For example, the pores of the porous carbon particle are about 10% of the volume of the carbon particle, including about 10% to about 60%, about 10% to about 50%, about 10% to about 40% of the volume of the carbon particle It can occupy about 80%.

  In some embodiments, porous carbon particles can include activated carbon particles. In some embodiments, porous carbon particles can include hierarchically structured carbon particles. In some embodiments, porous carbon particles can include structured carbon nanotubes, structured carbon nanowires, and / or structured carbon nanosheets. In some embodiments, porous carbon particles can include graphene sheets. In some embodiments, the porous carbon particles may be surface-treated carbon particles. For example, in the treated carbon particles, the number of one or more functional groups on one or more surfaces of the treated carbon may be reduced. For example, one or more functional groups are reduced by about 10% to about 60% (including about 20% to about 50% reduction) relative to the untreated carbon surface. The treated carbon may have a reduced number of hydrogen containing functional groups, nitrogen containing functional groups, and / or oxygen containing functional groups. In some embodiments, the treated carbon material has less than about 1% hydrogen containing functional groups, including less than about 0.5%. In some embodiments, the treated carbon material has less than about 0.5% nitrogen containing functional groups, including less than about 0.1%. In some embodiments, the treated carbon material has less than about 5% oxygen containing functional groups including less than about 3%. In some embodiments, the treated carbon material has less than about 30% hydrogen containing functional groups as compared to the untreated carbon material.

  In one embodiment, a mixture for producing an electrode of an energy storage device comprises a plurality of carbon particles and a plurality of elemental lithium metals, such as a plurality of elemental lithium metal particles. In some embodiments, the mixture is a dry particle mixture. In some embodiments, an electrode film for an electrode of an energy storage device comprises a dry particle mixture comprising a plurality of carbon particles, elemental lithium metal and one or more other electrode components such as a binder. it can. In some embodiments, an electrode film can be formed by dry processing from a dry particle mixture containing a plurality of carbon particles, elemental lithium metal, and one or more electrode components. As used herein, dry processing or dry mixture refers to treatments and mixtures that are free or substantially free of any liquid or solvent. For example, an electrode film formed from the dry particle mixture by dry processing may be substantially free of residue from such liquids and / or solvents. In some embodiments, wet processing is used, for example, to form a wet slurry solution to form an electrode film. In some embodiments, the electrode may be an anode of a lithium ion battery or lithium ion capacitor. For example, a lithium ion battery or lithium ion capacitor can include a cathode, an anode, and a separator between the cathode and the anode, the anode including a plurality of carbon particles and an electrode film containing elemental lithium metal. In some embodiments, the elemental metal is about 0.1 wt%, about 0.3 wt%, about 0.5 wt%, about 0.7 wt%, about 1 wt%, about 1.5 wt%, about 2 wt% of the electrode film mixture. About 2.5 wt%, about 3 wt%, about 3.5 wt%, about 4 wt%, about 4.5 wt%, about 5 wt%, about 6 wt%, about 7 wt%, about 8 wt%, about 9 wt% or It can be about 10% by weight. In certain embodiments, the elemental metal can comprise about 1% to about 5% by weight of the electrode film mixture.

  In some embodiments, the plurality of carbon particles and the elemental lithium metal comprises a plurality of lithium-carbon composite particles. For example, the lithium-carbon composite particles can include elemental lithium metal in the conductive porous carbon particles and the pores or hollow channels of the porous carbon particles. In some embodiments, the elemental lithium metal in the pores comprises elemental lithium metal particles. In some embodiments, the elemental lithium metal in the pores comprises resolidified elemental lithium metal. The porous carbon particles may be mesoporous carbon particles. In some embodiments, the porous carbon particles may be activated carbon particles or hierarchically structured carbon particles. In some embodiments, the plurality of lithium-carbon composite particles comprises a plurality of porous carbon particles in which at least some of the pores receive some elemental lithium metal. In some embodiments, the plurality of lithium-carbon composite particles comprises a plurality of porous carbon particles having pores that are filled or substantially filled with elemental lithium metal. As described in further detail herein, in some embodiments, the plurality of lithium-carbon composite particles comprises porous carbon particles and elemental lithium metal particles at a pressure below atmospheric pressure and above room temperature Manufactured by mixing at temperature. In some embodiments, porous carbon particles and elemental lithium metal particles can be mixed at temperatures near ambient temperature and at atmospheric pressure near atmospheric pressure. Porous carbon particles and elemental lithium particles are mixed under inert conditions, for example in a container such as a mixing container, to form a plurality of lithium-carbon composite particles, while being exposed only to an inert gas such as argon. It can be done. In some embodiments, mixing the porous carbon particles and the elemental lithium particles can include exposing the porous carbon particles and the elemental lithium particles to a carbonate vapor or carbonate liquid. In some embodiments, the plurality of lithium-carbon composite particles comprises a solid electrolyte interface (SEI) layer on elemental lithium metal in the opening of the outer surface of the particle. In some embodiments, forming the SEI layer includes exposing the plurality of lithium-carbon composite particles to carbonate vapor. For example, exposed elemental lithium metal in the openings of the pores of the outer surface of the particle can react with the carbonate vapor, thereby forming or substantially exposing the SEI layer only on the exposed elemental lithium metal It is formed only on the element lithium metal. In further embodiments, the SEI layer is ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), vinyl carbonate (VC), propylene carbonate (PC), combinations thereof, And / or reaction products of one or more carbonates selected from equivalents may be included. In further embodiments, the SEI layer can include a conductive polymer as provided herein.

  In another embodiment, the plurality of carbon particles and elemental lithium metal comprises a mixture containing elemental lithium metal and graphite particles. In some embodiments, the elemental lithium metal comprises a plurality of elemental lithium metal particles. In some embodiments, the elemental lithium metal comprises a coating of elemental lithium metal on at least some of one or more surfaces of the graphite particles. For example, the mixture may be a homogeneous or substantially homogeneous mixture comprising graphite particles and a coating of elemental lithium metal particles and / or elemental lithium metal on the surface of the graphite particles. The mixture can be formed using bulk elemental lithium metal. For example, the bulk elemental lithium metal can be reduced in size to a coating of at least some surfaces of a plurality of elemental lithium metal particles and / or graphite particles of a desired size. In some embodiments, graphite particles and bulk elemental lithium metal are blended to reduce the size of the bulk elemental lithium metal to obtain a mixture containing graphite particles and elemental lithium metal.

  Disclosed herein is a method of manufacturing a pre-doped electrode for use in an energy storage device. In some embodiments, a pre-lithiated electrode or an electrode pre-doped with a desirable amount of lithium metal containing one or more of the compositions described herein has improved energy density performance It is demonstrated that In some embodiments, an electrode containing one or more of the compositions described herein can be configured to compensate for the irreversible capacity loss exhibited by the energy storage device after the first charge and discharge cycle. . For example, an amount of elemental lithium metal added to the porous carbon particles and / or mixed with the graphite particles can be prelithiated or predoped to the desired degree, for example to compensate for the irreversible capacity loss to the desired degree .

  Also provided is an energy storage device in which both the anode and the cathode are pre-doped. In such embodiments, the anode and cathode may be pre-doped with metal ions without a separate pre-doping step. For example, in the case of an energy storage device comprising a first electrode comprising an electrode film containing an elemental metal as described herein and a second electrode, the second electrode may be pre-doped without a separate pre-doping step Good. Specifically, when in contact with the electrolyte, the elemental metal of the first electrode diffuses to the second electrode and becomes the pre-doped ion source of the second electrode. In some embodiments, the method of making a pre-doped energy storage device may not include a separate pre-doping step.

  Although the specification is primarily described with respect to lithium metal, the devices and / or processing methods described herein may be used to obtain compositions comprising carbon and lithium and / or one or more other metals. It may apply. For example, the devices and / or processes described herein may be applied to obtain compositions comprising one or more of lithium, sodium, potassium, magnesium and aluminum. Embodiments can be practiced including one or more of these metals in the "elemental" state, which is defined and used herein as "elemental lithium metal."

  In some embodiments, an electrode active material, such as carbon particles, and an elemental metal can be combined with one or more other electrode film components to provide an electrode film mixture. One or more other electrode film components can include a binder and / or one or more other electrode active material components (hereinafter referred to as electrode active components). In some embodiments, the binder can include a fibriltable binder, such as, for example, a fibriltable polymer. In some embodiments, the binder comprises a fibrillated fluoropolymer, such as polytetrafluoroethylene (PTFE). In some embodiments, the binder comprises PTFE, perfluoropolyolefin, polypropylene, polyethylene, copolymers thereof, and / or polymer mixtures thereof. In some embodiments, the electrode film mixture contains a binder consisting of a single binder material, such as a fibrillated fluoropolymer. For example, the electrode film mixture may contain only a single binder material, which is, for example, PTFE. In some embodiments, the one or more other electrode active components are hard carbon, soft carbon, graphene, mesoporous carbon, silicon, silicon oxide, tin, tin oxide, germanium, antimony, lithium titanate, titanium dioxide, Mixtures, alloys, composites of the above materials, and / or the like can be included. In certain embodiments, the electrode film mixture consists essentially of elemental metal particles, carbon particles, and fibrillatable binder particles. In a particular embodiment, the electrode film mixture consists of elemental metal particles, carbon particles, and fibrillated binder particles.

  FIG. 1 is a schematic view of a side cross section of an example energy storage device 100. In some embodiments, energy storage device 100 may be an electrochemical device. In some embodiments, the energy storage device 100 can be an energy storage device based on lithium, sodium, potassium, magnesium and / or aluminum. In some embodiments, energy storage device 100 may be a lithium based battery, such as a lithium ion battery. In some embodiments, the energy storage device 100 may be a lithium based capacitor such as a lithium ion capacitor. Of course, other energy storage devices are included within the scope of the present invention and may include capacitor-battery hybrids and / or fuel cells. The energy storage device 100 may include a first electrode 102, a second electrode 104, and a separator 106 disposed between the first electrode 102 and the second electrode 104. For example, the electrodes 104 of the first electrodes 102 and 2 may be provided adjacent to each other on the facing surfaces of the separator 106.

  The first electrode 102 may include a cathode, the second electrode 104 may include an anode, or the like. In some embodiments, the first electrode 102 can include the cathode of a lithium ion capacitor. In some embodiments, the first electrode 102 can include a cathode of a lithium ion capacitor, and the second electrode 104 can include an anode of a lithium ion capacitor. In a further embodiment, the first electrode 102 can comprise the cathode of a lithium ion battery and the second electrode 104 can comprise the anode of the lithium ion battery.

  The energy storage device 100 can include an electrolyte 122 that facilitates the transfer of ions between the two electrodes 102, 104 of the energy storage device 100. For example, the electrolyte 122 may be in contact with the first electrode 102, the second electrode 104, and the separator 106. The electrolyte 122, the first electrode 102, the second electrode 104, and the separator 106 may be contained within the housing 120 of the energy storage device. For example, the housing 120 of the energy storage device may be sealed after inserting the first electrode 102, the second electrode 104, and the separator 106 and filling the energy storage device 100 with the electrolyte 122, eg, The first electrode 102, the second electrode 104, the separator 106, and the electrolyte 122 may be physically sealed from the outside of the housing 120.

  Separator 106 can be configured to electrically insulate the two electrodes separated by the separator. For example, the separator 106 electrically isolates two electrodes arranged on opposite sides of the separator 106, such as the first electrode 102 and the second electrode 104, while allowing ion transfer between the two electrodes Can be configured to

  As shown in FIG. 1, the first electrode 102 and the second electrode 104 respectively include a first current collector 108 and a second current collector 110. The first current collector 108 and the second current collector 110 can facilitate electrical coupling between corresponding electrodes and an external circuit (not shown).

  The first electrode 102 includes a first electrode film 112 (e.g., an upper electrode film) on a first surface of the first current collector 108 (e.g., the upper surface of the first current collector 108), and a first current collector A second electrode film 114 (e.g., a lower electrode film) on a second opposing surface of 108 (e.g., the lower surface of the first current collector 108) may be provided. Similarly, the second electrode 104 includes a first electrode film 116 (e.g., an upper electrode film) on a first surface of the second current collector 110 (e.g., an upper surface of the second current collector 110) A second electrode film 118 may be provided on the second opposing surface of the current collector 110 (e.g., the lower surface of the second current collector 110). For example, the first surface of the second current collector 110 is a first collection such that the separator 106 is adjacent to the second electrode film 114 of the first electrode 102 and the first electrode film 116 of the second electrode 104. It can face the second surface of the current collector 108. The electrode films 112, 114, 116 and / or 118 can have various suitable shapes, sizes, and / or thicknesses. For example, the electrode film can have a thickness of about 60 μm to about 1,000 μm, including about 80 μm to about 150 μm.

  In some embodiments, electrode films such as the electrode films 112, 114, 116 and / or 118 described with reference to FIG. 1 comprise a plurality of carbon particles and a plurality of elemental lithium metals as set forth herein. It can contain elemental lithium metal such as particles, and the electrode film can be pre-doped or prelithiated with lithium. In certain embodiments, the plurality of electrode films 112, 114, 116 and 118 contain or are manufactured to include in the processing step an elemental metal and carbon mixture as provided herein. .

  In some embodiments, an electrode film having a plurality of carbon particles and an elemental lithium metal, the electrode pre-doped with a desired amount of lithium provides an energy storage device with improved energy performance. it can. For example, the electrodes may be pre-doped to compensate for the desired degree of irreversible capacity loss that occurs during the first charge and discharge of the energy storage device. In some embodiments, the electrode can have one or more electrode films containing a predetermined amount of lithium-carbon composite particles or a mixture of graphite particles and elemental lithium metal particles, whereby the energy storage device comprises It is demonstrated that irreversible capacity loss is reduced compared to energy storage devices that do not include pre-doped electrodes.

  As provided herein, in some embodiments, the plurality of carbon particles and the elemental lithium metal particles comprise a plurality of lithium-carbon composite particles. In some embodiments, the lithium-carbon composite particles comprise porous carbon particles having elemental lithium metal such as a plurality of elemental lithium metal particles in the pores.

  Exposed portions of elemental lithium metal may be covered with a protective SEI layer to reduce the possibility of unwanted chemical reactions of elemental lithium metal. The exposed portions of the elemental lithium metal described herein are exposed within the pores but under the corresponding outer surface of the porous carbon particle, or with the exposed but corresponding outer surface of the porous carbon particle It may be a portion that is substantially aligned, or a portion that protrudes from the pore cavity and the outer surface of each porous carbon particle. Thus, in some embodiments, elemental lithium particles can each comprise two parts: one essentially protected, for example by surface contact or by sealing, within the pores of the carbon particles The other is a non-exposed part which may be in the pore but without surface contact and which is an unsealed part, ie an exposed part which is not protected from external chemical reactions. For example, by forming and covering the SEI layer, exposed portions of the elemental lithium metal particles can reduce the possibility of unwanted external chemical reactions. The SEI layer can be produced by exposing elemental lithium-carbon particle mixture or elemental lithium-carbon composite particle mixture to carbonate vapor as indicated herein.

  FIGS. 2A-2F illustrate the introduction of elemental lithium metal, such as elemental lithium metal particles, into the pores of porous carbon particles, followed by a solid electrolyte interface (SEI) layer covering the exposed portions of the lithium elemental metal particles. FIG. FIG. 2A is a schematic cross-sectional view of an example of the porous carbon particle 200. As shown in FIG. 2A, porous carbon particles can have a plurality of hollow channels or pores 202 extending therethrough. FIG. 2B is a schematic cross-sectional view of the higher magnification porous carbon particle 200, showing a cross-sectional view of several hollow channels or pores 202 extending into the porous carbon particle 200. FIG. 2C is a schematic view showing the openings 204 on the outer surface of the porous carbon particle 200 corresponding to the hollow channels or pores 202 in the porous carbon particle 200. FIG. 2D is a schematic cross-sectional view of a hollow channel or pore 202 in a porous carbon particle 200 comprising elemental lithium metal 206. For example, elemental lithium metal 206 can include elemental lithium metal particles. For example, the hollow channels or pores 202 may be filled or substantially filled with elemental lithium metal 206. FIG. 2E shows an opening 204 on the outer surface of the porous carbon particle 200 corresponding to a hollow channel or pore 202 extending into the particle 200 and having elemental lithium metal 206 therein. FIG. 2F is a schematic diagram showing the SEI layer 208 on the exposed lithium metal 206 in the opening 202 of the outer surface of the porous carbon particle 200 shown in FIG. 2D.

  In some embodiments, some portions of elemental lithium metal, such as portions of elemental lithium in contact with the pore surface, may also be ionized by one or more components of the one or more pore surfaces Good. For example, some portions of elemental lithium are reacted and oxidized with one or more components of the pore surface of the carbon particle to participate in the electron transfer reaction, while the remaining portion of elemental lithium metal is zero Can maintain its oxidation state.

As discussed herein, porous carbon particles such as those described with reference to FIG. 2 have a cumulative particle size D ₅₀ of about 1 μm to about 20 μm, including about 1 μm to about 15 μm or about 1 μm to about 10 μm. You can have In some embodiments, porous carbon particles can have pores with a diameter of about 2 nm to about 2 μm. In some embodiments, porous carbon particles can have pores with a diameter of about 2% to about 10% of the diameter of the particles. In some embodiments, the pores of the porous carbon particles can occupy about 10% to about 80% of the volume of the carbon particles. In some embodiments, the size of the elemental lithium particles can be selected based on the pore size of the porous carbon particles such that the desired amount of elemental lithium metal can be inserted into the pores of the porous carbon particles .

  As described in further detail herein, in some embodiments, exposed portions of elemental lithium metal in the openings of the outer surface of the corresponding porous carbon particles can be exposed to carbonate vapor. The vapor can react with the exposed lithium metal to form a protective SEI layer covering the exposed elemental lithium metal portion. For example, the SEI layer can cover the elemental lithium metal portion exposed at the openings of the pores near or at the outer surface of the porous carbon particles. The SEI layer may be formed by the reaction of lithium metal and carbonate vapor. In some embodiments, for example, up to about 50%, about 40% or about 30%, only a portion of the outer surface of the porous carbon particles is covered by the SEI layer. In some embodiments, the SEI layer is formed only on exposed lithium metal or substantially only on exposed lithium metal, while the carbon portion of the outer surface of the lithium-carbon composite particle Is free of, or substantially free of, the SEI layer. In some embodiments, the SEI layer allows transport of electrons and ions therethrough while reducing or preventing further reaction of the lithium metal with the external environment, wherein lithium-carbon particles are used as part of the electrode When used, lithium metal electrochemical energy can be promoted to be utilized. The SEI layer can then maintain its original state while handling the lithium-carbon composite particles. Thus, the lithium-carbon composite particles allow elemental lithium metal to be used as a feedstock in wet or dry processing while reducing the possibility of undesirable reactions of elemental lithium.

  In another embodiment, the plurality of carbon particles and elemental lithium metal particles comprise a mixture comprising graphite particles and elemental lithium metal particles. As described in more detail herein, a mixture containing graphite particles and elemental lithium metal particles comprises combining graphite particles with bulk elemental lithium metal to reduce the particle size of the bulk elemental lithium metal, and It is also possible to obtain a mixture containing particles and elemental lithium metal particles of the desired size. In some embodiments, the graphite particles and the lithium metal particles form a homogeneous or substantially homogeneous mixture.

  Graphite particles and bulk elemental lithium metal can be combined under processing conditions equivalent to those described for lithium carbon composite particles. Graphite particles and bulk elemental lithium metal can be mixed with a binder in a dry process and compressed without using solvents or other liquids to form free standing films. In such embodiments, the risk of reactivity or explosion that is inherent when using such components for film formation in wet processing can be avoided.

As discussed herein, bulk elemental lithium metal can have a volume of greater than about 1 mm ³ . Bulk elemental lithium metal can be reduced in size to provide elemental lithium metal particles. In some embodiments, the elemental lithium metal particles can have a cumulative particle size D ₅₀ of about 0.5 μm to about 10 μm. In some embodiments, the elemental lithium metal particles can have a cumulative particle size D ₅₀ of about 1 μm to about 10 μm, or about 1 μm to about 5 μm. For example, one or more pieces of bulk elemental lithium metal may be reduced in size from about 1 mm ³ in volume to about 0.5 μm to about 10 μm by one or more of the treatments described herein. It may be a plurality of elemental lithium particles having a particle diameter D _50. In some embodiments, the mixture containing graphite particles and elemental lithium metal particles have a cumulative particle diameter D ₅₀ of the graphite particles and about 0.5μm~ about 10μm with a cumulative particle diameter D ₅₀ of about 1μm~ about 20μm Contains elemental lithium metal particles.

(Method)
FIG. 3 shows an exemplary process 300 for preparing a mixture containing a plurality of carbon particles and elemental lithium metal. In some embodiments, the process of forming the plurality of lithium-carbon composite particles comprises process 300. In some embodiments, a process step for forming a mixture containing a plurality of graphite particles and a plurality of elemental lithium metal particles comprises process step 300. Carbon particles can be provided as shown in block 302 of FIG. For example, the carbon particles can include porous carbon particles for preparing lithium-carbon composite particles, or graphite particles for preparing a mixture containing graphite and lithium metal.

  At block 304, elemental lithium metal is provided. In some embodiments, lithium particles are provided to form lithium-carbon composite particles. In some embodiments, bulk elemental lithium metal is provided to prepare a mixture containing graphite and lithium metal. At block 306, carbon particles and elemental lithium metal can be combined to provide a mixture containing a plurality of carbon particles and elemental lithium metal. The mixture can include a dry particle mixture. For example, the elemental lithium metal particles can be mixed with the porous carbon particles such that the elemental lithium metal particles are inserted into the pores of the porous carbon particles to form a lithium-carbon composite particle. For example, bulk elemental lithium metal and graphite particles can be mixed to reduce the size of bulk elemental lithium metal. In some embodiments, the bulk elemental lithium metal can be reduced to provide lithium metal particles of a desired size, and to provide a mixture containing lithium metal particles and graphite particles. In some embodiments, at least a portion of the bulk elemental lithium metal can be melted while reducing the size of the bulk elemental lithium metal, the molten lithium metal being at least a portion of some of the graphite particles Can form a coating.

  Process step 300 is the temperature, pressure, and / or inert conditions described herein with respect to the process steps of forming lithium-carbon composite particles and / or the process steps of forming a mixture of lithium metal and graphite particles. Can be done with In some embodiments, at least a portion of process step 300 includes the use of a carbonated liquid or vapor. In some embodiments, at least a portion of process step 300 can be performed under an atmosphere comprising carbonate vapor and / or under exposure to a carbonate liquid of carbon and elemental lithium metal. For example, combining porous carbon particles and elemental lithium metal can be performed under an atmosphere comprising carbonate vapor, for example, by exposing the porous carbon particles and elemental lithium metal to carbonate vapor. For example, combining porous carbon particles and elemental lithium metal can include exposing the porous carbon particles and elemental lithium metal to a carbonate liquid. In some embodiments, exposing the molten elemental lithium metal to a carbonate vapor and / or carbonate liquid promotes a reduction in surface tension of the molten elemental lithium metal, thereby, for example, melting the elemental lithium metal Improve the wettability of metal and lead elemental lithium metal to the pores of porous carbon particles.

  FIG. 4 shows an example of a process 400 for producing a plurality of lithium-carbon composite particles. At block 402, a plurality of porous carbon particles can be provided. As described herein, in some embodiments, the porous carbon particles are conductive carbon particles. In some embodiments, the plurality of porous carbon particles can include one or more activated carbon particles and / or hierarchically structured carbon particles. In some embodiments, the plurality of porous carbon particles can comprise structured carbon nanotubes, structured carbon nanowires and / or structured carbon nanosheets. In some embodiments, the plurality of porous carbon particles can include graphene sheets. In some embodiments, the plurality of porous carbon particles are mesoporous. In some embodiments, the plurality of porous carbon particles consist of, or consist essentially of, activated carbon particles. In some embodiments, the plurality of porous carbon particles consists of, or consists essentially of mesoporous particles. In some embodiments, the plurality of porous carbon particles consist of hierarchically structured carbon particles, or consist essentially of hierarchically structured carbon particles. In some embodiments, porous carbon particles may be surface-treated carbon particles, or other types of carbon particles as described herein.

  At block 404, a plurality of porous carbon particles can be combined with a plurality of elemental lithium metal particles to obtain a plurality of lithium-carbon composite particles. Here, elemental lithium metal is present in the pores of the plurality of lithium-carbon composite particles. In some embodiments, at least some of the pores in the plurality of porous carbon particles comprise elemental lithium metal. In some embodiments, at least some of the pores are filled or substantially filled with elemental lithium metal. In some embodiments, all or substantially all of the pores are filled with elemental lithium metal or substantially filled with elemental lithium metal. In some embodiments, the elemental lithium metal in the pores of the porous carbon particles comprises elemental lithium metal particles.

  In some embodiments, porous carbon particles and elemental lithium metal particles can be mixed in the mixing chamber of the mixing device to insert elemental lithium metal into the pores of the porous carbon particles. In some embodiments, elemental lithium metal particles are inserted into the pores. In some embodiments, the elemental lithium metal particles are at least partially melted during the mixing process, and the molten elemental lithium metal is at a low pressure or vacuum, eg, by capillary action, and / or within the mixing chamber. Is inserted into the pore. For example, molten elemental lithium metal may solidify once in the pores after the porous carbon particles have cooled. In some embodiments, the pores can include elemental lithium metal particles and / or resolidified elemental lithium metal. For example, the pores may be filled or substantially filled with elemental lithium metal particles and / or resolidified elemental lithium metal.

  In some embodiments, combining the plurality of porous carbon particles and the plurality of elemental lithium metal particles comprises the use of a carbonate liquid or vapor. For example, carbonate liquid or carbonate vapor can be supplied to the mixing device. In some embodiments, combining the plurality of porous carbon particles and the plurality of elemental lithium metal particles can be performed under an atmosphere comprising carbonate vapor, or exposing carbon and elemental lithium metal to a carbonate liquid Including. As described herein, exposure to the carbonate vapor or carbonate liquid promotes a reduction in surface tension of the molten elemental lithium metal, thereby, for example, enhancing the wettability of the molten elemental lithium metal; The element lithium metal is introduced into the pores of the porous carbon particles. In some embodiments, the carbonate vapor or carbonate liquid is ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), vinyl carbonate (VC), propylene carbonate (PC) And / or at least one of these equivalents.

  In some embodiments, devices configured to provide the desired mixing of elemental lithium particles and porous carbon particles include ribbon mixers, rotary mixers, planetary mixers, high shear blenders, ball mills, hammer mills, jet mills. , Resonant acoustic mixers, microwave mixers, and / or airflow mixers.

  In some embodiments, the size of the elemental lithium metal particles can be selected based on the pore size of the porous carbon material. For example, the particle size of the elemental lithium metal particles can be selected to facilitate the insertion of the desired amount of lithium metal particles into the pores of the porous carbon particles. In some embodiments, the pores of the porous carbon particles can be filled or substantially filled with lithium metal particles. As an example of porous carbon particles, the average diameter of the pores is about 1/50 to 1/10 of the average carbon particle diameter, and about 10% to about 80% of the volume of the carbon particles are branched particles. Mention may be made of inner pore networks. The corresponding elemental lithium metal particles can be selected to be small enough in maximum outside diameter to enter the pores of the carbon particles. In some embodiments, the elemental lithium metal particles are selected to have an average diameter less than the average diameter of the pores of the plurality of porous carbon particles.

In some embodiments, porous carbon particles and elemental lithium metal particles can be mixed under a pressure less than atmospheric pressure. For example, porous carbon particles and elemental lithium metal particles can be supplied to the internal volume of the mixing chamber of the device and mixed under a pressure of about 1 × 10 ⁻⁸ Pa to about 1 × 10 ⁵ Pa. In some embodiments, porous carbon particles and elemental lithium metal particles can be mixed at temperatures above room temperature, such as temperatures above about 20.degree. In some embodiments, the temperature may be 20 ° C to 200 ° C, including 50 ° C to 180 ° C. In some embodiments, mixing the porous carbon particles and the elemental lithium metal particles under subatmospheric pressure and above room temperature facilitates insertion of the lithium metal particles into the porous carbon particles. Become.

  In some embodiments, a gas such as an inert gas can be supplied to the mixing chamber during mixing of the carbon particles and the lithium metal particles. The inert gas can include a noble gas such as argon. In some embodiments, the mixing chamber is flushed with an inert gas to facilitate insertion of lithium metal into the pores of the porous carbon particles. In some embodiments, an inert gas can be flowed during at least a portion of performing the mixing step. In some embodiments, the flow of inert gas can be initiated after mixing of the porous carbon particles and the lithium metal particles has begun. In some embodiments, the inert gas is reacted only during the second half of the mixing step, eg, only between about the last 40%, about 30%, about 20%, about 10% or about 5% of the last mixing step. Flow into the chamber. In some embodiments, the inert gas can be flowed for the entire time the mixing step is being performed, or for substantially the entire time. The time for flowing the inert gas can be selected so that the insertion of the lithium metal particles into the pores of the porous carbon particles is at a desired level.

  At block 406, a solid electrolyte interface (SEI) layer can be formed on the exposed portion of lithium metal in the lithium-carbon composite particles. For example, a SEI layer can be formed on exposed portions of elemental lithium metal underlying the outer surface of the corresponding porous carbon particles. The SEI layer reduces or prevents the degree of exposure of that portion of the lithium metal to components of the external environment such as oxygen and / or water that can degrade the lithium metal while ionizing ions therethrough And / or enable transport of electrons. In some embodiments, forming the SEI layer comprises exposing the lithium-carbon composite particles to a vapor containing one or more vaporized electrolyte solvents of an energy storage device. In some embodiments, the vapor comprises carbonate vapor. In some embodiments, the carbonate vapor is ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), vinyl carbonate (VC), propylene carbonate (PC), these And / or their equivalents.

  In some embodiments, other protective coatings, such as conductive polymer coatings, can be formed on the exposed portions of lithium metal. In some embodiments, low vapor pressure polymerization of monomers can form a conductive polymer coating on exposed portions of lithium metal. For example, pyrrole can be used as a precursor monomer to produce a polymer coating comprising polypyrrole. In some embodiments, the polymer coating can comprise polythiophene, polyfuran, polyaniline, polyacetylene, or combinations thereof, and / or the like.

  In some embodiments, the lithium-carbon composite particles can be exposed to carbonate vapor after the desired amount of lithium metal has been inserted into the porous carbon particles. In some embodiments, lithium-carbon composite particles may be exposed to carbonate vapor in the mixing chamber, for example, to the internal volume of the mixing chamber. The carbonate-containing solvent can be vaporized and fed to the mixing chamber after mixing so that the vapor can react with the exposed portion of lithium metal to form the SEI layer. In some embodiments, lithium-carbon particles can be transported to different chambers, where the particles can be exposed to carbonate vapor. Exposure of the lithium-carbon composite particles to carbonate vapor results in conditions of various temperatures and pressures at which the carbonate can remain in the gas phase or substantially in the gas phase such that the carbonate vapor can react with lithium metal. It can be done below. In some embodiments, the pressure of the internal volume can be maintained below the vapor pressure of the carbonate or carbonate mixture at the temperature of the internal volume.

  As described herein, in some embodiments, exposure to carbonate vapor can be performed during the mixing of the plurality of porous carbon particles and the elemental lithium metal, and forming the SEI layer While continuing. For example, exposure to carbonate vapor can facilitate both the insertion of lithium metal into the pores of the carbon particles and the formation of the SEI layer.

  In some embodiments, the carbon portion of the outer surface of the lithium-carbon composite material is free or substantially free of the SEI layer, and elemental lithium metal exposed only or substantially exposed on exposed elemental lithium metal The carbonate-containing vapor can be reacted only with elemental lithium metal or substantially only with elemental lithium metal, such that the SEI layer is formed only on the. In some embodiments, the SEI layer can protect the exposed lithium metal, thereby subsequent treatment of the lithium-carbon composite particles, and / or electrode films and / or lithium-carbon composite particles. Or manufacture of an electrode film mixture can be made easy. In some embodiments, the SEI layer can allow for both ion and electron transport while reducing or preventing further reaction of lithium metal with the external environment. Transport of ions and electrons in the SEI layer allows access to conductive lithium metal in the porous carbon particles during operation of the energy storage device, lithium without first breaking or breaking the porous carbon particles. Facilitate access to electrical energy of origin. In some embodiments, the SEI layer suppresses or prevents the reaction of the exposed lithium metal with the liquid, thereby lithium-carbon composite particles in a wet or dry electrode manufacturing process, such as a process comprising a slurry solution. To facilitate the use of

  Referring to FIG. 5, a process step 500 for preparing a mixture using bulk elemental lithium metal and graphite is described. At block 502, a bulk elemental lithium metal can be provided. As described herein, bulk elemental lithium metal can include sheets and / or chunks of elemental lithium metal, or other forms of bulk metal. At block 504, graphite particles can be provided. At block 506, bulk elemental lithium metal and graphite particles can be combined to provide a mixture containing elemental lithium metal and graphite particles.

  In some embodiments, combining the bulk elemental lithium metal and the graphite particles comprises reducing the size of the bulk elemental lithium metal. In some embodiments, the combining step reduces the size such that the bulk elemental lithium metal is a desired size of elemental lithium particles and is homogeneous or contains elemental lithium metal particles and graphite particles. A substantially homogeneous mixture can be obtained. In some embodiments, at least a portion of the lithium metal can be melted while reducing the size of the bulk elemental lithium metal, and the molten lithium metal coats at least a portion of some of the graphite particles It can be made to form. In some embodiments, the mixture comprising graphite particles and elemental lithium metal comprises a coating of graphite particles, a plurality of elemental lithium metal particles, and / or elemental lithium on the surface of at least some of the graphite particles. For example, the mixture may comprise a homogeneous or substantially homogeneous mixture containing graphite particles, elemental lithium metal particles and / or elemental lithium metal on one or more surfaces of at least some of the graphite particles.

  In some embodiments, combining the bulk elemental lithium metal and the graphite particles comprises blending the bulk elemental lithium metal and the graphite particles. In some embodiments, a Waring® blender can be used. In some embodiments, the blend of bulk elemental lithium metal and graphite particles can be selected to obtain lithium metal particle size and a homogenous or substantially homogeneous mixture. In some embodiments, the conditions of the mixing process include the duration of the mixing process, the magnitude of the shear force, the temperature of the mixing process, the speed of the mixing blade and / or paddle tip, the type of mixer, the mixing chamber, It can be adjusted by the environment, the order in which the materials are introduced into the mixing chamber, and / or the amount of material introduced into the mixing chamber.

  In some embodiments, materials other than graphite or materials other than graphite added to graphite can be mixed with bulk elemental lithium metal. For example, one or more other electrode film materials can be combined with bulk elemental lithium metal to obtain a homogeneous or substantially homogeneous mixture containing elemental lithium metal particles of the desired size. In some embodiments, the one or more other materials are silicon, silicon oxide, tin, tin oxide, carbon composites containing carbon, silicon and tin, combinations thereof, and / or the like Can be included.

  In some embodiments, a mixture containing graphite particles and lithium metal particles can be used directly to form a dry particle electrode film in a dry manufacturing process. In some embodiments, a mixture containing graphite particles and elemental lithium metal can then be treated to form a SEI layer around the lithium metal particles, thereby, for example, lithium metal and the external environment. Further reaction with can be reduced or prevented. In some embodiments, one or more processes to form the SEI layer described with reference to FIG. 4 can be applied. For example, the mixture may be exposed to a vaporized electrolyte solvent, such as, for example, carbonate vapor. In some embodiments, the carbonate vapor may have one or more of the compositions described herein. In some embodiments, the above processes can facilitate the use of lithium metal in wet processing steps, such as wet slurry processing to form electrode films.

  FIG. 6 shows an example of a dry process step 600 for producing an electrode film of an energy storage device comprising carbon particles and elemental lithium metal. For example, the electrode film can comprise a plurality of lithium-carbon composite particles or a mixture of graphite particles and elemental lithium metal. In some embodiments, the electrode may be an electrode of the energy storage device 100 described with reference to FIG. In some embodiments, the electrode comprises an anode of a lithium ion battery. In some embodiments, the electrode comprises an anode of a lithium ion capacitor.

  At block 602, carbon particles and elemental lithium metal can be provided. In some embodiments, the step of providing the elemental lithium metal and carbon particles comprises providing a plurality of lithium-carbon composite particles. In some embodiments, providing elemental lithium metal and carbon particles comprises providing a mixture containing elemental lithium metal and graphite particles. In some embodiments, a mixture containing a plurality of lithium-carbon composite particles and / or elemental lithium particles and graphite particles can be made according to one or more processing steps described herein. In some embodiments, block 602 includes the steps described in block 302, block 304, block 402, and / or block 502.

  At block 604, carbon particles and elemental lithium metal can be combined with one or more other electrode film components to obtain an electrode film mixture. In some embodiments, one or more other electrode film components include a binder and / or one or more other electrode active components. In some embodiments, the binder can include a fibriltable binder, including, for example, a fibrillatable polymer. In some embodiments, the binder comprises a fibrillated fluoropolymer, such as polytetrafluoroethylene (PTFE). In some embodiments, the binder comprises PTFE, perfluoropolyolefin, polypropylene, polyethylene, copolymers thereof, and / or blends of polymers thereof. In some embodiments, the electrode film mixture contains a binder that consists of a single binder, such as a fibrillated fluoropolymer. For example, the electrode film mixture may contain only a single binder, which may be PTFE. In some embodiments, one or more other electrode active components are: hard carbon, soft carbon, graphene, mesoporous carbon, silicon, silicon oxide, tin, tin oxide, germanium, lithium titanate, titanium dioxide, and the like Mixtures or composites of materials and / or equivalents thereof. In some embodiments, block 604 includes the steps described in block 306, block 404, block 406, and / or block 506. In particular embodiments, block 604 includes the steps of block 406. Thus, in some embodiments, block 604 includes forming a SEI layer that includes exposing the lithium-carbon composite particles to a vapor comprising one or more vaporized electrolyte solvents of an energy storage device.

  In some embodiments, the combining step of block 604 is a dry process. For example, elemental lithium metal particles and carbon particles can be combined with one or more other electrode film components in a dry process, ie, a process that is free or substantially free of solvents or additives, to obtain a dry particle electrode A film mixture can be obtained. In some embodiments, a mixture comprising a plurality of lithium-carbon composite particles or elemental lithium metal particles and graphite particles is combined with one or more other components of the energy storage device electrode in a dry mixing process. Thus, a dry particle electrode film mixture can be obtained. Thus, in some embodiments, block 604 can include combining elemental lithium metal particles and carbon particles with a fibrilatable binder.

  At block 606, an electrode film comprising the electrode film mixture can be obtained. For example, the electrode film may be a film used for a lithium ion battery or an anode of a lithium ion capacitor. In some embodiments, the electrode film mixture contains a fibrillatable binder, and the formation of the electrode film comprises a fibrillation process. In the fibrillation process, the fibrillatable binder can form a matrix, lattice and / or web of fibrils that structurally support other components of the electrode film. For example, a free standing dry particle electrode film can be formed from the electrode film mixture by fibrillating the binder material in the electrode film mixture. In some embodiments, shear forces can be applied to the binder material to form fibrils, such as in a blending process. For example, grinding treatment including jet milling can be performed.

  In certain embodiments, the free-standing electrode film consists essentially of elemental metal particles, carbon particles, and fibrillated binder particles. In certain embodiments, a free standing electrode film is comprised of elemental metal particles, carbon particles, and fibrillated binder particles. In further embodiments, the elemental metal particles and the carbon particles are composite particles as set forth herein.

  In some embodiments, the electrode film can be formed by a wet process to make an electrode of an energy storage device. In some embodiments, a wet processing step for producing an electrode of an energy storage device comprises the steps of preparing a liquid solution containing one or more electrode components comprising an electrode active component, and the liquid solution And forming an electrode film. In some embodiments, the step of forming the electrode using the liquid solution comprises slot die coating, gravure coating, reverse roll coating, knife over roll coating, metering rod coating, curtain coating and / or dip coating. Use one or more.

  In some embodiments, the electrode, eg, an electrode of a lithium ion battery or lithium ion capacitor, includes one or more electrode films produced in one or more steps of steps 300, 400, 500 and / or 600. For example, the electrode can include one or more electrode films coupled to a current collector. For example, the electrodes can include respective electrode films bonded to opposite surfaces of the current collector. In some embodiments, a dry particle electrode film may be bonded to the surface of the current collector, and is directly bonded to the current collector, such as by a lamination process. In some embodiments, an intervening adhesive layer can facilitate bonding of the electrode film to the current collector. Thus, provided is a method of manufacturing a pre-doped electrode for use in an energy storage device comprising one or more of process steps 300, 400, 500 and / or 600. For example, the energy storage device may, as in process step 300, provide carbon particles, provide elemental metal, combine the carbon particles with elemental lithium metal, and mix the carbon particles and elemental lithium metal in a mixture. Obtaining a plurality of porous carbon particles and mixing a plurality of porous carbon particles with a plurality of elemental lithium metal particles, as in process step 400. It can be manufactured by a method comprising the steps of: obtaining a plurality of lithium-carbon composite particles; and forming a solid electrolyte interface layer on the exposed portion of lithium metal of the lithium-carbon composite particles As in 500, the steps of providing bulk elemental lithium metal, providing graphite particles, mixing bulk elemental lithium metal and graphite particles Combining to obtain a mixture containing elemental lithium metal and graphite particles, and / or providing carbon particles and elemental lithium metal as in process step 600. A method comprising: combining the carbon particles and elemental lithium metal with one or more other electrode film components to obtain an electrode film mixture; and forming an electrode film comprising the electrode film mixture. It can be manufactured.

  In some embodiments, the energy storage device can be manufactured using one or more electrode films described herein. For example, the electrodes of the energy storage device can include one or more electrode films as described herein. In some embodiments, the energy storage device may comprise an outer housing. An electrode comprising one or more of the above electrode films can be inserted into the interior of the housing. In some embodiments, one or more other electrodes and / or one or more separators may be inserted internally. Thereafter, the housing may be sealed after the desired amount of electrolyte has been introduced into the housing of the energy storage device.

  FIG. 7 is a schematic view of an example of an apparatus 700 configured to prepare one or more of the compositions described herein. For example, the device 700 may also include a mixing device configured to produce bulk material for use in producing the electrodes of the energy storage device, such as the electrodes described with reference to FIG. Good. As shown in FIG. 7, carbon particles 702 and elemental lithium metal 704 may be mixed chambers of apparatus 700 such that carbon particles 702 and elemental lithium metal 704 may be mixed according to one or more processing steps described herein. An internal volume of 706 may be provided. The apparatus 700 can be configured to obtain a mixture containing a plurality of lithium-carbon composite particles or graphite particles and elemental lithium metal according to one or more processing steps described herein. For example, the device 700 mixes the carbon particles 702 and the elemental lithium metal 704 according to the process steps described with reference to FIGS. 3 to 6 and lithium having lithium metal in the pores of the corresponding porous carbon particles Constructing to provide a mixture containing carbon composite particles or lithium metal (elemental lithium metal coating formed on at least some of the surfaces of elemental lithium metal particles and / or graphite particles, etc.) and graphite particles Can. In some embodiments, apparatus 700 includes a ribbon mixer, a rotary mixer, a planetary mixer, a high shear blender, a ball mill, a hammer mill, a jet mill, a resonant acoustic mixer, a microwave mixer, and / or an air flow mixer. Can.

  8A-8C are photographs illustrating various steps in the process of preparing a dry particle mixture from bulk elemental lithium metal, according to one embodiment. FIG. 8A shows graphite particles and a lithium metal sheet in the mixing chamber of a mixing apparatus (eg, a Waring® blender). In this example, about 23.3 grams (grams) of graphite powder and about 0.68 grams of bulk elemental lithium metal are combined in a blender. Graphite powder and lithium metal were blended about 36 times at a pulse interval of about 5 seconds. In FIG. 8C, about 1.7 g of PTFE was added to the blended mixture containing graphite powder and lithium metal. PTFE, graphite powder and lithium metal were blended about 24 times with a pulse interval of about 5 seconds to obtain an electrode film mixture containing PTFE, graphite powder and lithium metal.

FIGS. 9A and 9B are graphs showing the electrochemical performance of two coin half cells comprising free standing electrode films formed using the example PTFE, graphite powder and a mixture containing lithium metal. The half cell further included a lithium metal counter electrode, a polyolefin separator, and an electrolyte containing LiPF ₆ in a carbonate based solvent. Figures 9A and 9B show the change in voltage of the coin half cell after the first delithiation step without the pre-constant current lithiation step. The graphs of FIGS. 9A and 9B show voltage in volts (V) on the y-axis and delithiation capacity in amperes-hour (Ah) on the x-axis. These voltage curves estimate the amount of electrochemically available lithium metal (e.g., in free standing electrode films formed using a mixture containing PTFE, graphite powder and lithium metal) at the electrodes of the device can do. The coin half cell corresponding to FIG. 9A exhibited a capacity of about 2.5 milliamp hours at a cutoff voltage of 1.5 V and the coin half cell corresponding to FIG. 9B exhibited a capacity of approximately 3 milliamp hours at the same cutoff voltage .

  The delithiation performance may depend on the amount of lithium metal that is electrochemically available at the graphite composite electrode. The amount of lithium metal contributes as several roles in the supply of electrochemical energy. For example, lithium metal contributes to the electrochemical energy for SEI formation on the graphite surface, and to the redox reaction for intercalation of lithium ions of graphite and free lithium metal. For example, FIG. 9A shows the presence of free lithium metal in the graphite electrode film and the presence of intercalated lithium ions. The delithiation process, with a voltage near zero, from 0.0 milliamp hours to about 1 milliamp hour in FIG. 9A can be effected by free lithium metal. On the other hand, the increase in voltage from about 1 milliamp hour to about 2.5 milliamp hour can be attributed to the deintercalation process of lithium ions in the graphite. FIG. 9B, in contrast to FIG. 9A, is that the voltage is about 0.1 volt at the start of the delithiation process, so in the delithiation process, lithium ion deintercalation in graphite is almost exclusively Support the possibility of happening. These two examples make it easy to adjust the robustness of the dry electrode formation process to adapt bulk lithium metal and the capacity from the bulk lithium metal at the final electrode to the desired value, for example by the input amount To demonstrate the performance that can be done.

  Using the mixing apparatus shown in FIG. 7 and FIGS. 8A-8C, or other apparatus suitable for mixing a carbon material with a bulk elemental lithium material, see, for example, FIGS. 3-6 described herein. It will be appreciated that alternative methods to those described above can be implemented to form bulk electrode materials, films, and / or energy storage devices.

  Headings (titles) as used herein are used for reference and to locate the various sections. These headings do not limit the scope of the described concepts. These concepts may be applicable throughout the specification.

  The disclosed embodiments are provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. It can be done. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

While the foregoing description points out novel features of the present invention as applied to various embodiments, one skilled in the art will recognize that various omissions, substitutions and changes in the form and details of the described apparatus or method may be made. It will be understood that it is possible without departing from the scope of the invention.

Claims (38)

A first electrode, a second electrode, and a separator between the first electrode and the second electrode,
An energy storage device, wherein at least one of the first electrode and the second electrode comprises carbon particles and an elemental metal. The carbon particle comprises porous carbon particles, each porous carbon particle having a plurality of pores, at least some of the plurality of pores receiving at least some of the elemental metal. Energy storage equipment. The energy storage device according to claim 2, wherein the porous carbon particles contain activated carbon. The energy storage device according to claim 2, wherein the porous carbon particles contain hierarchically structured carbon. The energy storage device according to claim 2, wherein the porous carbon particles contain mesoporous carbon. The energy storage device of claim 2, further comprising a solid electrolyte interface (SEI) layer covering the exposed portion of the elemental metal. The energy storage device according to claim 5, wherein the SEI layer covers the exposed portion of the elemental metal underlying the outer surface of the corresponding porous carbon particle. 6. The energy storage device of claim 5, wherein at least one of the first electrode and the second electrode comprises a dry electrode film containing elemental metal and carbon particles. The energy storage device of claim 1, wherein the carbon particles comprise graphite particles. The energy storage device of claim 1, wherein at least one of the first electrode and the second electrode comprises an anode. The energy storage device according to claim 10, wherein the anode is a lithium ion battery or a lithium ion capacitor anode. The energy storage device of claim 1, wherein the elemental metal comprises elemental lithium metal particles. A method of manufacturing an energy storage device, comprising
Combining an elemental lithium metal and a plurality of carbon particles to form an electrode film mixture;
Forming an electrode film from the electrode film mixture. Forming a first electrode and a second electrode at least one of which includes the electrode film and a current collector;
The method according to claim 13, further comprising: inserting a separator between the first electrode and the second electrode. 15. The method of claim 14, wherein the plurality of carbon particles comprises a plurality of porous carbon particles, each porous carbon particle having a plurality of pores. 16. The method of claim 15, wherein the plurality of porous carbon particles comprise at least one of activated carbon and hierarchically structured carbon. In the step of mixing the elemental lithium metal and the plurality of carbon particles, the at least some of the plurality of pores receive at least some of the plurality of elemental lithium metals, the elemental lithium metal and the plurality of the plurality of pores. The method according to claim 15, comprising the step of mixing the porous carbon particles. The method of claim 17 further comprising the step of forming a solid electrolyte interface (SEI) layer on the exposed portion of the elemental lithium metal. The method according to claim 18, wherein forming an SEI layer comprises covering an exposed portion of the elemental lithium metal underlying the outer surface of the corresponding porous carbon particle. 19. The method of claim 18, wherein forming an SEI layer comprises exposing exposed portions of the elemental lithium metal to an electrolyte solvent vapor. 21. The method of claim 20, wherein the exposing the exposed portion of elemental lithium to the electrolyte solvent vapor comprises exposing the exposed portion of elemental lithium to carbonate vapor. The method of claim 13, wherein the plurality of carbon particles comprises a plurality of graphite particles. 23. The method of claim 22, wherein the electrode film mixture is a substantially homogeneous mixture. The above element lithium metal includes an element lithium metal particle,
Manufacturing bulk elemental lithium metal;
And D. reducing the size of the bulk elemental lithium metal to form a plurality of elemental lithium metal particles. The method according to claim 13, wherein the step of combining the elemental lithium metal and the plurality of carbon particles comprises the step of combining a dry elemental lithium metal and a plurality of dry carbon particles to form a dry electrode film mixture. 15. The method of claim 14, wherein at least one of the first electrode and the second electrode comprises a lithium ion battery or lithium ion capacitor anode. 15. The method of claim 14, further comprising disposing the first electrode, the separator and the second electrode in a housing. 28. The method of claim 27, further comprising the steps of adding an electrolyte into the housing and contacting the electrolyte to the first electrode and the second electrode. 29. The method of claim 28, wherein the step of contacting the first electrode and the second electrode comprises pre-doping the second electrode. A mixture of bulk materials for producing a lithium ion energy storage device,
With elemental lithium metal,
A mixture containing activated carbon particles.   31. A mixing device having an internal volume comprising the mixture of claim 30. 32. The mixing device according to claim 31, wherein the internal volume comprises an inert gas. 32. The mixing device of claim 31, wherein the activated carbon particles comprise graphite. 32. The mixing device according to claim 31, wherein the activated carbon particles include porous carbon particles having the element lithium metal in the pores. 35. The mixing device of claim 34, further comprising a vapor of an electrolyte solvent in the interior volume.   A pre-doped electrode for use in an energy storage device comprising a mixture according to claim 30. Combining an elemental lithium metal and a plurality of carbon particles to form an electrode film mixture;
Forming a first electrode film from the electrode film mixture.   An energy storage device manufactured by a process comprising the method according to any one of claims 13-29.